Android-将RGB彩色图转换为灰度图

Android-将RGB彩色图转换为灰度图

实例：RGB2Grey

项目运行效果图：

源代码：

public class MainActivity extends Activity {    /* (non-Javadoc)     * @see android.app.Activity#onCreate(android.os.Bundle)     */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        //通过Id来获取界面中组件的引用        Button rgb2greyBtn  = (Button) findViewById(R.id.rgb2greybtn);        ImageView imageView1 = (ImageView) findViewById(R.id.imageView1);        final ImageView imageView2 = (ImageView) findViewById(R.id.imageView2);         //通过位图工厂，创建一个位图        final Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.ic_android);        imageView1.setImageBitmap(bitmap);        //为“转换为灰度图”按钮添加监听事件        rgb2greyBtn.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {// TODO Auto-generated method stub//将转换过后的灰度图显示出来imageView2.setImageBitmap(convertGreyImg(bitmap));}});            }        /**     * 将彩色图转换为灰度图     * @param img 位图     * @return返回转换好的位图     */    public Bitmap convertGreyImg(Bitmap img) {    int width = img.getWidth();//获取位图的宽    int height = img.getHeight();//获取位图的高        int []pixels = new int[width * height];//通过位图的大小创建像素点数组        img.getPixels(pixels, 0, width, 0, 0, width, height);    int alpha = 0xFF << 24;     for(int i = 0; i < height; i++){    for(int j = 0; j < width; j++) {    int grey = pixels[width * i + j];        int red = ((grey  & 0x00FF0000 ) >> 16);    int green = ((grey & 0x0000FF00) >> 8);    int blue = (grey & 0x000000FF);        grey = (int)((float) red * 0.3 + (float)green * 0.59 + (float)blue * 0.11);    grey = alpha | (grey << 16) | (grey << 8) | grey;    pixels[width * i + j] = grey;    }    }    Bitmap result = Bitmap.createBitmap(width, height, Config.RGB_565);    result.setPixels(pixels, 0, width, 0, 0, width, height);    return result;    }}

布局文件：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/LinearLayout1"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" ><ImageView     android:id="@+id/imageView1"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_gravity="center_horizontal"    /><Button     android:id="@+id/rgb2greybtn"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:text="@string/rgb2greybtn"    android:layout_gravity="center_horizontal"/><ImageView     android:id="@+id/imageView2"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_gravity="center_horizontal"    />"</LinearLayout>